We thank Dr Valdivia for his comments. We fully support and invite the surgical community to participate in a dedicated programme of explant analysis supported by scientific societies. Data obtained from ex vivo evaluations are mandatory in order to improve the knowledge of device behaviour in humans and to improve the manufacture of next generation devices.1
As mentioned by Dr Valdivia, this analysis did not include clinical data, such as neck anatomy, but it was impossible to obtain more clinical data a posteriori. This highlights that any new device should be part of a post-market study protocol and surveillance plans should be anticipated in order to track in vivo failures that could result in serious adverse health outcomes.2 Such observations could facilitate understanding of the in vivo behaviour of devices and provide information on the mechanisms responsible for delayed degradation or failure.3
We also agree that only descriptive data were presented, as the analysis of two cases could not allow for the provision of objective data concerning failure modes or mechanisms. Once again, this highlights that dedicated, independent, and transparent explant analysis programmes are needed, in order to provide large scale epidemiological data, and allow the analyses of degradation phenomena, whereas the analysis of only few explants can be highly biased. This is also why we decided to publish all new observations on explanted devices to meet our values of independence and transparency. Moreover, this will help physicians in their choices by cross referencing results with clinical variables to determine which are the best indications for a specific use. Consequently, analysing a large number of explants of a specific device could help in distinguishing between sporadic events and general behaviour, and in providing information on the mechanisms responsible for degradation and failure.
In conclusion, sophisticated devices are becoming more common in the endovascular era. Accordingly, it is mandatory to ensure closer and systematic control on the durability of such complex devices.
References
- 1.Lejay A., Colvard B., Magnus L., Dion D., Georg Y., Papillon J. Explanted vascular and endpvascular graft analysis: where do we stand and what should we do? Eur J Vasc Endovasc Surg. 2018;55:567–576. doi: 10.1016/j.ejvs.2018.01.022. [DOI] [PubMed] [Google Scholar]
- 2.Wanhainen A., Verzini F., Van Herzeele I., Allaire E., Bown M., Cohnert T. European Society for Vascular Surgery (ESVS) 2019 clinical practice guidelines on the management of abdominal aorto-iliac artery aneurysms. Eur J Vasc Endovasc Surg. 2019;57:8–93. doi: 10.1016/j.ejvs.2018.09.020. [DOI] [PubMed] [Google Scholar]
- 3.Chakfe N., Heim F. What do we learn from explant analysis programs? Eur J Vasc Endovasc Surg. 2017;54:133–134. doi: 10.1016/j.ejvs.2017.05.018. [DOI] [PubMed] [Google Scholar]